Public transit, especially urban rail systems, plays a vital role in shaping commuting patterns. Compared with census data and survey data, large-scale and real-time big data can track the impacts of ...urban policy implementations at finer spatial and temporal scales. Therefore, this study proposed a multi-level analytical framework using transit smartcard data to examine urban commuting dynamics in response to rail transit upgrades. The study area was Shenzhen, one of the most highly urbanized and densely populated cities in China, which provides the opportunity to examine the effects of rail transit upgrades on commuting patterns in a rapidly developing urban context. Changes in commuting patterns were examined at three levels: city, region, and individual. At the city level, we considered the average commuting time, commuting speed, and commuting distance across the whole city. At the region level, we analyzed changes in the job accessibility of residential zones. Finally, this study evaluated the potential effects of rail transit upgrades on the jobs-housing relationship at the individual level. Difference-in-difference models were used for causal inference between rail transit upgrades and commuting patterns. In the very short term, the opening of new rail transit lines resulted in no significant changes in overall commuting patterns across the whole city; however, two effects of rail transit upgrades on commuting patterns were identified. First, rail transit upgrades enhanced regional connectivity between residential zones and employment centers, thus improving job accessibility. Second, rail transit improvement increased the commuting distances of individuals and contributed to the separation of workplaces and residences. This study provides meaningful insights into the effects of rail transit upgrades on commuting patterns.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Porous materials for C2H2/CO2 separation mostly suffer from high regeneration energy, poor stability, or high cost that largely dampen their industrial implementation. A desired adsorbent should have ...an optimal balance between excellent separation performance, high stability, and low cost. We herein report a stable, low‐cost, and easily scaled‐up aluminum MOF (CAU‐10‐H) for highly efficient C2H2/CO2 separation. The suitable pore confinement in CAU‐10‐H can not only provide multipoint binding interactions with C2H2 but also enable the dense packing of C2H2 inside the pores. This material exhibits one of the highest C2H2 storage densities of 392 g L−1 and highly selective adsorption of C2H2 over CO2 at ambient conditions, achieved by a low C2H2 adsorption enthalpy (27 kJ mol−1). Breakthrough experiments confirm its exceptional separation performance for C2H2/CO2 mixtures, affording both large C2H2 uptake of 3.3 mmol g−1 and high separation factor of 3.4. CAU‐10‐H achieves the benchmark balance between separation performance, stability, and cost for C2H2/CO2 separation.
An ultra‐microporous Al‐MOF with suitable pore confinement enables the dense packing of C2H2 molecules for efficient C2H2/CO2 separation, exhibiting the benchmark balance between high separation performance, low cost, high stability, and large‐scale synthesis for industrial applications.
HIV envelope protein gp120 is considered a primary molecular determinant of viral neutralization phenotype due to its critical role in viral entry and immune evasion. The intrinsically disordered ...regions (IDRs) in gp120 are responsible for their extensive sequence variations and significant structural rearrangements. Despite HIV neutralization phenotype and sequence/structural information of gp120 have been experimentally characterized, there remains a gap in our understanding of the correlation between the viral phenotype and IDRs in gp120. Here, we combined machine learning (ML) techniques and molecular dynamics (MD) simulations to gain data-driven and molecule-mechanism insights into relationships between viral sequence, structure, and phenotypes from the perspective of IDRs in gp120. ML models, trained only on the length and disorder score of IDRs, achieved equivalent performance to the best baseline model using amino acid sequences to discriminate HIV neutralization phenotype, indicating that the lengths or disorder of specific IDRs are strongly related to HIV neutralization phenotypes. Comparative MD analysis reveals that gp120 with extreme neutralization phenotypes in multiple conformational states, especially some IDRs, exhibit significantly distinct structural dynamics, conformational flexibility, and thermodynamic distributions. Taken together, our study provided insights into the role of IDRs in gp120 responding to HIV neutralization phenotypes, which will advance the understanding of molecular mechanisms underlying viral function associated with HIV neutralization phenotype and help develop antiviral vaccines or drugs.
•Combining machine learning techniques and molecular dynamics simulations to gain data-driven and molecule-mechanism insights.•Exploring relationships between viral sequence, structure, and phenotypes from the perspective of intrinsically disordered regions (IDRs) in gp120.•Identifying lengths or disorder of specific IDRs are strongly related to HIV neutralization phenotypes.•Revealing gp120 with extreme neutralization phenotypes exhibits significantly distinct structural dynamics, conformational flexibility, and thermodynamic distributions.
Antimony sulfide (Sb2S3) is emerging as a promising light harvesting material owing to its brilliant photoelectric property. However, the performance of Sb2S3‐based solar cells is partly limited by ...serious back contact interface recombination and hole transportation resistance. High‐efficiency Sb2S3 devices typically use Spiro‐OMeTAD and/or Au as back contact materials, but their stability and cost are a concern. In this sense, a surface modification scheme by lithium‐doping is first introduced for Sb2S3 via a facile molten salt method. The ions in the molten state have high mobility and activity, enabling doping reactions to complete within a short time. The lithium‐doped Sb2S3 thin film has a smooth and well‐bonded surface, preferred (hk1) orientations, and an upshifted valence band maximum (VBM), which favors the hole extraction. Finally, a device using carbon as an electrode, which is more than a dozen times cheaper than gold, raises the short‐circuit current density (JSC) from 12.35 to 14.40 mA cm−2, and the power conversion efficiency (PCE) from 4.47% to 6.16%. This is among the highest PCE reported for full‐inorganic Sb2S3 solar cells, which demonstrates a facile interface modification technique via molten alkali salt to improve the performance of Sb2S3 solar cells.
Sb2S3 is a kind of new light‐absorbing material possessing high stability in ambient environment, high absorption coefficient in the visible range, and abundant elemental storage. Here, a surface modification scheme by lithium‐doping is first introduced for Sb2S3 via a facile molten salt method. The device with the low‐cost carbon electrode delivers a power conversion efficiency (PCE) of 6.16%, which is among the highest PCE reported for the full‐inorganic Sb2S3 solar cells.
A novel severe acute respiratory syndrome human coronavirus (SARS HCoV) was identified from respiratory illness patients (named SARS-CoV-2 by ICTV) in December 2019 and has recently emerged as a ...serious threat to world public health. However, no approved drugs have been found to effectively inhibit the virus. Since it has been reported that HIV protease inhibitors can be used as anti-SARS drugs by targeting SARS-CoV-1 3CLpro, we chose six approved anti-HIV drugs and investigated their binding interactions with 3CLpro to evaluate their potential to become clinical drugs for the new coronavirus pneumonia (COVID-19) caused by SARS-CoV-2 infection. The molecular docking results indicate that the 3CLpro of SARS-CoV-2 has a higher binding affinity for all the studied inhibitors than does SARS-CoV-1. Two docking complexes (indinavir and darunavir) with high docking scores were further subjected to MM-PBSA binding free energy calculations to detail the molecular interactions between these two protease inhibitors and SARS HCoV 3CLpro. Our results show that, among the inhibitors tested, darunavir has the highest binding affinity with SARS-CoV-2 and SARS-CoV-1 3CLpro, indicating that it may have the potential to be used as an anti-COVID-19 clinical drug. The mechanism behind the increased binding affinity of HIV protease inhibitors toward SARS-CoV-2 3CLpro (as compared to SARS-CoV-1) was investigated by MD simulations. Our study provides insight into the possible role of structural flexibility during interactions between SARS HCoV 3CLpro and inhibitors and sheds light on structure-based design of anti-COVID-19 drugs targeting SARS-CoV-2 3CLpro.
A novel severe acute respiratory syndrome human coronavirus (SARS HCoV) was identified from respiratory illness patients (named SARS-CoV-2 by ICTV) in December 2019 and has recently emerged as a serious threat to world public health.
Leydig cell tumor (LCT) is a rare testicular tumor. We report a case of an elderly male patient who discovered a left testicular mass during a regular health examination four years ago. The patient ...did not experience any significant discomfort and opted for regular follow‐up visits. During the most recent visit, we performed routine ultrasound and contrast‐enhanced ultrasound (CEUS) examinations. By observing the lesion's location, echogenicity, margins, vascular distribution, as well as the rapid enhancement and slow washout characteristics on contrast‐enhanced ultrasound, we arrived at a diagnosis of LCT. Subsequently, the patient underwent left inguinal orchiectomy. Postoperative pathology and immunohistochemistry confirmed the diagnosis of LCT. Additionally, we conducted a comprehensive review of LCT‐related literature from PubMed and SCOPUS, summarizing the clinical features, follow‐up duration, prognosis, and ultrasound characteristics associated with LCT.
This article describes a rare case of testicular Leydig cell tumor and provides an analysis of the case using roution ultrasound, color Doppler ultrasound, and contrast‐enhanced ultrasound. Relevant literature from recent years was also reviewed to summarize the typical ultrasound features, clinical characteristics, and prognosis of testicular Leydig cell tumors.
Boron compound BOMes2 containing an internal B−O bond undergoes highly efficient photoisomerization, followed by sequential structural transformations, resulting in a rare eight‐membered B, ...O‐heterocycle (S. Wang, et al. Org. Lett. 2019, 21, 5285–5289). In this work, the detailed reaction mechanisms of such a unique carbonyl‐supported tetracoordinate boron system in the first excited singlet (S1) state and the ground (S0) state were investigated by using the complete active space self‐consistent field and its second‐order perturbation (MS‐CASPT2//CASSCF) method combined with time‐dependent density functional theory (TD‐DFT). Moreover, an imine‐substituted tetracoordinated organic boron system (BNMes2) was selected for comparative study to explore the intrinsic reasons for the difference in reactivity between the two types of compounds. Steric factor was found to influence the photoisomerization activity of BNMes2 and BOMes2. These results rationalize the experimental observations and can provide helpful insights into understanding the excited‐state dynamics of heteroatom‐doped tetracoordinate organoboron compounds, which facilitates the rational design of boron‐based materials with superior photoresponsive performances.
MS‐CASPT2//CASSCF calculations reveal detailed mechanisms for the photoisomerization of boron compounds, showing that the steric hindrance influences their photoisomerization activity.
In this study, two metal–viologen complexes, formulated as Cd 1.5 (H 2 L) 0.5 (Cl) 3 (CH 3 OH) n ( 1 ) and Eu 2 (L)(NO 3 ) 4 (HOCH 2 CH 2 OH) 2 n ( 2 ), were constructed by a tetracarboxylate ...anchored bipyridinium-based ligand 1,1′-bis(3,5-dicarboxybenzyl)-4,4′-bipyridinium dichloride (H 4 L·Cl 2 ). Single-crystal X-ray analyses revealed that complex 1 featured a 2D-layered structure, while complex 2 showed a 1D “ladder-like” chain structure. The difference in the central metal ions, anions, solvent molecules, deprotonation degree of the tetracarboxylate ligand, coordination modes and conformations of the ligand have a great influence on the final structure. As expected, incorporation of the viologen moiety to the frameworks led to the predefined photochromism: when samples 1 and 2 were exposed to UV-visible light, a reversible color change from light yellow to blue/dark blue occurred. Moreover, complex 2 exhibited the characteristic emission of Eu( iii ) ion in the visible region, and it also displayed an interesting reversible tunable photo-induced luminescence switching behavior: under the irradiation of UV-vis light, the luminescence emission intensity of complex 2 gradually decreased and reached 15% of the starting value after 8 min. These results may not only help to further understand the structure–photoresponse relationships of viologen-based MOFs, but also help to guide the design and synthesis of luminescent materials with photo-modulated switching ability.
The stability of high-energy-density lithium metal batteries depends on the uniformity of solid electrolyte interphase (SEI) on lithium metal anodes. Rationally improving SEI uniformity is hindered ...by poorly understanding the effect of structure and components of SEI on its uniformity. Herein, a bilayer structure of SEI formed by isosorbide dinitrate (ISDN) additives in localized high-concentration electrolytes was demonstrated to improve SEI uniformity. In the bilayer SEI, LiN
O
generated by ISDN occupies top layer and LiF dominates bottom layer next to anode. The uniformity of lithium deposition is remarkably improved with the bilayer SEI, mitigating the consumption rate of active lithium and electrolytes. The cycle life of lithium metal batteries with bilayer SEI is three times as that with common anion-derived SEI under practical conditions. A prototype lithium metal pouch cell of 430 Wh kg
undergoes 173 cycles. This work demonstrates the effect of a reasonable structure of SEI on reforming SEI uniformity.
In recent years, perovskite solar cells have been considerably developed, however the lead in the absorber MAPbI3 is a potential threat to the environment. To explore potential alternatives, the ...structural and electronic properties of MAGeX3 (X = Cl, Br, I) were investigated using different density functional theory methods, including GGA-PBE, PBE-SOC, HSE06 and HSE-SOC. The results implied that MAGeI3 exhibits an analogous band gap, substantial stability, remarkable optical properties, and significant hole and electron conductive behavior compared with the so far widely used absorber MAPbI3. Moreover, the calculations revealed that the energy splitting resulting from the spin-orbit coupling is evident on Pb, moderate on Ge, I and Br, and negligible on Cl. Our work not only sheds some light on screening novel absorbers for perovskite solar cells but also deepens the understanding of these functional materials.
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